- Education and Science»
- Astronomy & Space Exploration
Take an Astrophotography Picture of Jupiter
Jupiter Opposition 2016
The Earth will lap Jupiter once again on March 8th, 2016 – when it reached its closest point to us. This closest point is called opposition and is marked by Jupiter rising at sunset and setting at sunrise. Jupiter is the solar system’s largest planet and always makes a great astrophotography object. Its moons regularly pass in front of and behind the planet and the atmosphere is always changing. The Great Red Spot never disappoints and Jupiter’s brightness makes it easy to find and photograph. On occasion, an object will strike Jupiter and leave a temporary scar. Jupiter pictures can be taken in even the brightest of cities because Jupiter itself is so bright that it just doesn’t matter.
Wesley Impact on Jupiter - July 2009
How Do I Get Ready?
Finding Jupiter is always pretty easy as it’s the brightest object in its part of the sky (only Venus is brighter). King Jupiter will travel in the same part of the sky as the Sun in the summertime. For us in the northern hemisphere, that means it will be high in the sky which eliminates a lot of the atmosphere you have to photograph through. Less atmosphere means more brightness and less atmospheric turbulence – great for better pictures.
It’s located in the constellation Leo this time and is about halfway in between the bright stars Regulus in the constellation Leo and Spica in the constellation Virgo. You can find Spica by following the arc in the Big Dipper handle to Arcturus (bright star in constellation Bootes) and speeding straight over to Spica. Several websites have finder charts to help you plan when to photograph it (examples are Astronomy and Sky and Telescope). I’ve used a free program called Home Planet for years – it even shows the sky’s view as viewed toward the horizon (just like standing and looking). There are also software packages that can be purchased and smart phone apps as well. I have Star Chart and Planet finder on my phone.
Before opposition, you might be better off waking up early than staying up late since Jupiter is well positioned in the early morning hours. At opposition: staying up late will give you the best opportunities. After opposition, you can catch Jupiter earlier and earlier in the evening.
Jupiter With Its Four Large Moons
What Do I Need to Have?
The most important thing to have is a telescope that tracks the sky. Celestron, Orion, and Meade (among others) make such telescopes. For solar system objects like Jupiter, the higher the F number on the telescope, the higher the magnification (but the smaller the view of the sky). Planets are very tiny objects so you don’t a big view of the sky. You’ll also need a camera and a way to record the camera’s picture.
Note - F number for telescopes (distance the light travels divided by diameter of lens) is like F number for camera.
Note - I am simplifying some concepts and not going into subjects very deeply. So, optics or astrophotography experts may disagree with my words but the concepts are consistent with how most people think about things. There are quite a few websites that go into these subjects more deeply for those interested.
The first telescope picture I took of Jupiter was through a digital camera that was positioned to take the picture through the eyepiece of the telescope. This is called afocal photography. You could see the two main bands on Jupiter but that was about it. There are adapters that will hold your camera in place and many cameras have remotes or timers so that your telescope doesn’t shake when you snap the picture. The longer the eye relief that the eyepiece has, the easier it will be for your camera to find the focal plane. Eye relief is how far away from the eyepiece lens the image focuses (long eye relief is also good for eyeglass wearers). Orion Siruis Plossl 17mm and 20mm are good considerations.
Focusing the camera can be challenging – it should be set close to infinity. If the Moon is out, focus the camera on it and then go back to Jupiter (with or without the telescope). The smaller the image, the more in focus it is, in general. Then, your exposure has to be such that it is bright enough to see details but not so bright that the object is overexposed. If the image is big enough (like for the Moon definitely), the histogram function will be useful – sometimes it’s hard to use on a small object because there is so much black.
Note – if you have a DSLR with a high magnifying telephoto lens or a Point and Shoot with 18-20x zoom or higher, you can take some fairly interesting pictures (especially compared with the alternative). The image size will be small (look how small Jupiter is with your eyes for instance) but it will save you from getting a telescope. You can try adding a teleconverter if you have one. Tip - the larger the lens’ diameter the more light is captured and the more “zoom” you can use. Incidentally, my son thought my “dots” were nice but Jupiter was a little bigger than that – although the moons were dots.... (usually four dots).
Jupiter with Zoom Digital Camera (no telescope)
How Can I Make My Pictures a Little Better?
The next goal is to take as many pictures as possible in a short amount of time. Then, you can use stacking software such as Registax which imports your pictures and combines them into one better picture. You only have about 3 minutes until Jupiter will have rotated too much to combine your pictures properly. Jupiter has the shortest day in the solar system and it rotates very quickly – thus increasing the challenge. Experiment with the movie taking function of your camera.
Jupiter Taken Afocally and Multiple Images Stacked
How Can I Make My Picture Better Still?
The next thing to try is prime focus photography. The telescope eyepiece is just one more thing that gets in the way between your camera and Jupiter. With prime photography, the eyepiece is not used. This where the higher F number telescopes become important since there is no camera lens or telescope eyepiece to help magnify the planet (although an image magnifier can be used).
If you already have a DSLR camera with a removable lens then you can get an adapter to mount it directly to your telescope. A 1.25” adapter is fine for planetary astrophotography. If you ever want to take wide field pictures of the sky (which DSLR’s are good at) you may want to upgrade your telescope diagonal to a 2” diagonal since a 1.25” diagonal is too small for a DSLR Field of View.
You can also buy a separate color camera that is made specifically for astrophotography. Cameras good for planets can use a 1.25” diagonal. The key is to be able to take pictures quickly. For Jupiter, you can be overexposed in as little as 1/250th of a second at prime focus. So, you want to look at frames per second and get no less than 60 fps for Jupiter – if you have a big telescope. Of course, this will require a method to store the pictures since these cameras aren’t like a DSLR with memory. Most people store the pictures on a laptop.
How Can I Make My Picture A Little Better Still?
This gets to be a little bit like the “Shout” song. There is always more that you can do to get a little improvement – some of it is equipment, some of it is technique, and some of it is good atmospheric conditions.
I haven’t mentioned monochrome cameras that are made specifically for astrophotography yet. Monochrome cameras have an advantage over color cameras in that every pixel is used for the color band you are photographing (typically Red, Green and Blue for a planet like Jupiter). This involves using filters with your camera (since color cameras have the filters built inside). Since time is of the essence, a filter wheel is of great use so that you can switch filters quickly. Of course, it requires more post-processing to combine your images into a single color image.
I haven’t mentioned additional software packages with advanced processing features. I use Registax for image capture and initial processing. Then I move my RGB pictures individually to Maxim DL to combine and do some processing and then to Photoshop Elements for final tweaking. There is a lot of art mixed with this science to coax the most out of your pictures as possible.
I haven’t mentioned optimizing your magnification for your telescope using a Barlow or other image magnifiers with your camera. In short, the F number of your telescope, coupled with the camera pixel size, coupled with an image magnifier (such as a Barlow) will eventually reach a limit – otherwise you could make super huge pictures of Jupiter. So, you have to make sure your astrophotography setup’s combination is compatible with your telescope.
As to atmospheric conditions, there is a great website called Clear Dark Sky which will give you the “stillness” of the atmosphere (called seeing) and projected cloud cover for the next couple of days. It’s invaluable because if there is not great seeing, there are not great pictures.
Aperture (or diameter) of your telescope is key too. Fourteen inches is about the limit unless you use real-time adjustments for atmospheric volatility. Most days, you’ll be better off with a little less than fourteen inches. Eleven and twelve inch telescopes can be used quite often. Of course, you can always decrease the light capturing diameter on a big telescope but you can’t increase it on a smaller telescope. Aperture translates into dollars though and 6 to 8 inch telescopes can take very rewarding pictures too.
I may write another article with more of these advanced considerations but I also think that it’s better to stick a toe in the water before jumping in with both feet. So, this is enough to get you started and off on a potentially rewarding astrophotography journey. If Saturn is more to your liking, then I have tips and suggestions for you on my Saturn page too!
Jupiter with a Moon's Shadow Cast On It
Items for Astrophotograpy
This is the telescope I use for these pictures.